xwayland: Support cross DnD from Wayland (#8708)

Adds support for drag-and-drop from Wayland clients to XWayland ones

1 files changed, 211 insertions, 0 deletions

diff --git a/src/xwayland/Dnd.cpp b/src/xwayland/Dnd.cpp
new file mode 100644
index 00000000..488ee8dd
--- /dev/null
+++ b/src/xwayland/Dnd.cpp
@@ -0,0 +1,211 @@
+#include "Dnd.hpp"
+#include "XWM.hpp"
+#include "XWayland.hpp"
+#include "Server.hpp"
+#include "../managers/XWaylandManager.hpp"
+#include "../desktop/WLSurface.hpp"
+
+static xcb_atom_t dndActionToAtom(uint32_t actions) {
+    if (actions & WL_DATA_DEVICE_MANAGER_DND_ACTION_COPY)
+        return HYPRATOMS["XdndActionCopy"];
+    else if (actions & WL_DATA_DEVICE_MANAGER_DND_ACTION_MOVE)
+        return HYPRATOMS["XdndActionMove"];
+    else if (actions & WL_DATA_DEVICE_MANAGER_DND_ACTION_ASK)
+        return HYPRATOMS["XdndActionAsk"];
+
+    return XCB_ATOM_NONE;
+}
+
+eDataSourceType CX11DataOffer::type() {
+    return DATA_SOURCE_TYPE_X11;
+}
+
+SP<CWLDataOfferResource> CX11DataOffer::getWayland() {
+    return nullptr;
+}
+
+SP<CX11DataOffer> CX11DataOffer::getX11() {
+    return self.lock();
+}
+
+SP<IDataSource> CX11DataOffer::getSource() {
+    return source.lock();
+}
+
+void CX11DataOffer::markDead() {
+#ifndef NO_XWAYLAND
+    std::erase(g_pXWayland->pWM->dndDataOffers, self);
+#endif
+}
+
+void CX11DataDevice::sendDataOffer(SP<IDataOffer> offer) {
+    ; // no-op, I don't think this has an X equiv
+}
+
+void CX11DataDevice::sendEnter(uint32_t serial, SP<CWLSurfaceResource> surf, const Vector2D& local, SP<IDataOffer> offer) {
+#ifndef NO_XWAYLAND
+    auto XSURF = g_pXWayland->pWM->windowForWayland(surf);
+
+    if (offer == lastOffer)
+        return;
+
+    if (!XSURF) {
+        Debug::log(ERR, "CX11DataDevice::sendEnter: No xwayland surface for destination");
+        return;
+    }
+
+    auto SOURCE = offer->getSource();
+
+    if (!SOURCE) {
+        Debug::log(ERR, "CX11DataDevice::sendEnter: No source");
+        return;
+    }
+
+    xcb_set_selection_owner(g_pXWayland->pWM->connection, g_pXWayland->pWM->dndSelection.window, HYPRATOMS["XdndSelection"], XCB_TIME_CURRENT_TIME);
+
+    xcb_client_message_data_t data = {0};
+    data.data32[0]                 = g_pXWayland->pWM->dndSelection.window;
+    data.data32[1]                 = XDND_VERSION << 24;
+
+    // let the client know it needs to check for DND_TYPE_LIST
+    data.data32[1] |= 1;
+
+    std::vector<xcb_atom_t> targets;
+
+    for (auto& mime : SOURCE->mimes()) {
+        targets.emplace_back(g_pXWayland->pWM->mimeToAtom(mime));
+    }
+
+    xcb_change_property(g_pXWayland->pWM->connection, XCB_PROP_MODE_REPLACE, g_pXWayland->pWM->dndSelection.window, HYPRATOMS["XdndTypeList"], XCB_ATOM_ATOM, 32, targets.size(),
+                        targets.data());
+
+    g_pXWayland->pWM->sendDndEvent(surf, HYPRATOMS["XdndEnter"], data);
+
+    lastSurface = XSURF;
+    lastOffer   = offer;
+
+    auto hlSurface = CWLSurface::fromResource(surf);
+    if (!hlSurface) {
+        Debug::log(ERR, "CX11DataDevice::sendEnter: Non desktop x surface?!");
+        lastSurfaceCoords = {};
+        return;
+    }
+
+    lastSurfaceCoords = hlSurface->getSurfaceBoxGlobal().value_or(CBox{}).pos();
+#endif
+}
+
+void CX11DataDevice::sendLeave() {
+#ifndef NO_XWAYLAND
+    if (!lastSurface)
+        return;
+
+    xcb_client_message_data_t data = {0};
+    data.data32[0]                 = g_pXWayland->pWM->dndSelection.window;
+
+    g_pXWayland->pWM->sendDndEvent(lastSurface->surface.lock(), HYPRATOMS["XdndLeave"], data);
+
+    lastSurface.reset();
+    lastOffer.reset();
+
+    xcb_set_selection_owner(g_pXWayland->pWM->connection, g_pXWayland->pWM->dndSelection.window, XCB_ATOM_NONE, XCB_TIME_CURRENT_TIME);
+#endif
+}
+
+void CX11DataDevice::sendMotion(uint32_t timeMs, const Vector2D& local) {
+#ifndef NO_XWAYLAND
+    if (!lastSurface || !lastOffer || !lastOffer->getSource())
+        return;
+
+    const auto                XCOORDS = g_pXWaylandManager->waylandToXWaylandCoords(lastSurfaceCoords + local);
+
+    xcb_client_message_data_t data = {0};
+    data.data32[0]                 = g_pXWayland->pWM->dndSelection.window;
+    data.data32[2]                 = (((int32_t)XCOORDS.x) << 16) | (int32_t)XCOORDS.y;
+    data.data32[3]                 = timeMs;
+    data.data32[4]                 = dndActionToAtom(lastOffer->getSource()->actions());
+
+    g_pXWayland->pWM->sendDndEvent(lastSurface->surface.lock(), HYPRATOMS["XdndPosition"], data);
+    lastTime = timeMs;
+#endif
+}
+
+void CX11DataDevice::sendDrop() {
+#ifndef NO_XWAYLAND
+    if (!lastSurface || !lastOffer)
+        return;
+
+    // we don't have timeMs here, just send last time + 1
+    xcb_client_message_data_t data = {0};
+    data.data32[0]                 = g_pXWayland->pWM->dndSelection.window;
+    data.data32[2]                 = lastTime + 1;
+
+    g_pXWayland->pWM->sendDndEvent(lastSurface->surface.lock(), HYPRATOMS["XdndDrop"], data);
+
+    sendLeave();
+#endif
+}
+
+void CX11DataDevice::sendSelection(SP<IDataOffer> offer) {
+    ; // no-op. Selection is done separately.
+}
+
+eDataSourceType CX11DataDevice::type() {
+    return DATA_SOURCE_TYPE_X11;
+}
+
+SP<CWLDataDeviceResource> CX11DataDevice::getWayland() {
+    return nullptr;
+}
+
+SP<CX11DataDevice> CX11DataDevice::getX11() {
+    return self.lock();
+}
+
+std::vector<std::string> CX11DataSource::mimes() {
+    return mimeTypes;
+}
+
+void CX11DataSource::send(const std::string& mime, uint32_t fd) {
+    ;
+}
+
+void CX11DataSource::accepted(const std::string& mime) {
+    ;
+}
+
+void CX11DataSource::cancelled() {
+    ;
+}
+
+bool CX11DataSource::hasDnd() {
+    return dnd;
+}
+
+bool CX11DataSource::dndDone() {
+    return dropped;
+}
+
+void CX11DataSource::error(uint32_t code, const std::string& msg) {
+    Debug::log(ERR, "CX11DataSource::error: this fn is a stub: code {} msg {}", code, msg);
+}
+
+void CX11DataSource::sendDndFinished() {
+    ;
+}
+
+uint32_t CX11DataSource::actions() {
+    return supportedActions;
+}
+
+eDataSourceType CX11DataSource::type() {
+    return DATA_SOURCE_TYPE_X11;
+}
+
+void CX11DataSource::sendDndDropPerformed() {
+    ;
+}
+
+void CX11DataSource::sendDndAction(wl_data_device_manager_dnd_action a) {
+    ;
+}